[Xapian-discuss] identifying matched terms

Yes:

http://xapian.org/docs/apidoc/html/classXapian_1_1Enquire.html#a18

Hmm, it seems you should really be able to call methods on an
MSetIterator to get this information - the Enquire class isn't the most
logical place for them. I'll have a look and see if there's a good
reason why this is part of Enquire.

Cheers,
Olly

I finally got around to implementing this and I ran into another issue.
I'm using the xapian python bindings and whenever I call
positionlist_begin on a TermIterator, I get this:

File "/usr/lib/python2.4/site-packages/xapian.py", line 169, in
positionlist_begin
def positionlist_begin(*args): return
_xapian.TermIterator_positionlist_begin(*args)
RuntimeError: InvalidOperationError: positionlist_begin not supported

Which is consistent with the code I see here:
http://www.xapian.org/docs/sourcedoc/html/termlist_8h-source.html

I don't think I can implement what I want without the positionlist. My
document is composed of terms that come from several sources and I need
to know the position of the term to figure out which source a term came
from and then relay that information to the front-end which would
highlight the term in its unmodified form.

Is positionlist something planned for the next revision?

Thanks,
Jason T.

That's just the default implementation in the base class. We implement
positionlist_begin in the subclasses when appropriate (sometimes it
isn't - for example the listed of terms ignored as stopwords is
available from the QueryParser as a TermIterator, but there's no
document context there so positionlist_begin() doesn't make sense
at the conceptual level).

But it sounds like we've missed a case where it should work. I'll
take a look, but as a workaround you can get a positionlist from the
database by supplying the term and document id explicitly:

http://xapian.org/docs/apidoc/html/classXapian_1_1Database.html#a13

For the backends we currently have, that's as efficient as getting it
from the TermIterator would be.

Cheers,
Olly